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AC sizing, duct sizing, air changes, heat loss, fan laws, and HVAC calculators.
Calculate heating and cooling load from room dimensions, insulation, and climate zone.
Calculate AC tonnage from room sqft, ceiling height, and sun exposure.
Calculate duct diameter from CFM and air velocity.
Calculate CFM required from room volume and air changes per hour.
Calculate humidity ratio in grains per pound from temperature and RH.
Calculate heat loss in BTU per hour from wall area, R-value, and temp difference.
Calculate total refrigerant charge from line length and factory charge.
Calculate new CFM, pressure, and power from speed change using affinity laws.
Calculate coil capacity in BTU from CFM and entering/leaving temperatures.
Determine economizer mode from outside and return air temperatures.
Calculate BTU needed for heating or cooling a room by area.
Calculate radiator output needed from room volume and heat loss factor.
Calculate duct size from airflow CFM and velocity.
Estimate heating and cooling load from room dimensions.
Calculate BTU needed to heat or cool a room from its dimensions.
Estimate heat loss through walls, windows, and roof by area and R-value.
Estimate cooling load in tons from room size, occupants, and equipment.
Calculate air changes per hour from airflow CFM and room volume.
Calculate air velocity in a duct from CFM and duct dimensions.
Calculate static pressure drop in ductwork from length and fittings.
Reference guide for common HVAC filter sizes and MERV ratings.
Calculate refrigerant charge from line set length and system specs.
Plan thermostat setpoints by time of day to optimize energy savings.
Reference Energy Star efficiency ratings for HVAC equipment types.
Calculate annual cooling cost from SEER rating and cooling hours.
Calculate annual heating cost from HSPF rating and heating hours.
Calculate dehumidifier capacity from room size and moisture level.
Calculate humidifier capacity needed from room volume and target humidity.
Calculate required ventilation CFM from occupancy and room type.
Calculate heat pump coefficient of performance from output and input.
Calculate annual fuel cost savings from furnace AFUE upgrade.
Calculate radiant floor heating BTU output from floor area and temp.
Calculate baseboard heater wattage needed from room dimensions.
Determine correct ceiling fan diameter from room dimensions.
Calculate CFM from air velocity and duct cross-section area.
Convert cubic feet per minute to liters per second.
Convert liters per second to cubic feet per minute.
Reference for air handler units: components, sizing, and airflow configurations.
Reference for AHU components: coils, filters, dampers, and humidifiers.
Reference for chiller types: air-cooled, water-cooled, absorption, and centrifugal.
Reference for boiler types: fire-tube, water-tube, condensing, and electric boilers.
Reference for cooling towers: crossflow, counterflow, natural draft, and hybrid types.
Reference for heat recovery systems: HRV, ERV, run-around coils, and heat wheels.
Reference for variable air volume boxes: single duct, dual duct, and fan-powered types.
Reference for fan coil units: 2-pipe, 4-pipe, vertical, and horizontal configurations.
Reference for split system HVAC: components, sizing, and installation considerations.
Reference for mini split systems: single-zone, multi-zone, and BTU sizing guides.
Reference for window air conditioners: BTU ratings, EER, and installation types.
Reference for portable air conditioners: single-hose, dual-hose, and BTU ratings.
Reference for evaporative coolers: direct, indirect, and two-stage systems.
Reference for radiant floor heating: hydronic, electric, and air-based systems.
Reference for baseboard heaters: electric, hydronic, and sizing guidelines.
Reference for radiator types: cast iron, panel, column, and towel rail radiators.
Reference for convectors: natural, forced, and in-floor convector heaters.
Reference for unit heaters: gas-fired, electric, hot water, and steam types.
Reference for infrared heaters: high-intensity, low-intensity, and tube heaters.
Reference for pellet stoves: freestanding, inserts, BTU output, and hopper sizes.
Reference for wood stoves: catalytic, non-catalytic, EPA-certified, and sizing.
Reference for gas fireplaces: direct vent, vent-free, and B-vent types.
Reference for electric fireplaces: wall-mount, insert, freestanding, and linear types.
Reference for heat pump types: air-source, ground-source, water-source, and hybrid.
Reference for ground source heat pumps: horizontal, vertical, and pond loop systems.
Reference for air source heat pumps: ducted, ductless, COP ratings, and cold climate.
Reference for water source heat pumps: open loop, closed loop, and lake plate systems.
Reference for ductless HVAC systems: wall mount, ceiling cassette, and floor mount.
Reference for packaged HVAC units: gas/electric, heat pump, and dual-fuel packages.
Reference for rooftop HVAC units: constant volume, VAV, and make-up air units.
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